• 한국축산식품학회지
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• 제44권4호
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• pp.758-778
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• 2024

This study assessed previous research aimed at mitigating the adverse effects of freeze-thawing on meat quality. Specifically, it focuses on assessing the physicochemical alterations in meat resulting from freezing, freeze-thawing, or technologies to minimize these alterations. Recent studies have focused on conventional freeze-thaw technology applicable across various livestock species and muscle types. However, recent research has indicated the necessity for developing freeze-thaw technology considering the unique characteristics of individual muscles. In this review, we summarize previous studies that have compared alterations in the physicochemical properties of primary muscles owing to freezing or freeze-thawing. Despite the introduction of various technologies to significantly reduce the adverse effects on meat quality resulting from freeze-thawing, it is essential to consider the unique characteristics (proximate composition, pH, and muscle fiber characteristics) of individual muscles or cuts to develop enhanced the freeze-thaw processing technology.

• 한국임상수의학회지
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• 제19권1호
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• pp.80-85
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• 2002

This study was performed to investigate the freezomg condition especially focused on extender composition to achieve good post-thaw viability and motility of canine sperm. Semen were collected from 6 male dogs which had been proved to be fertile in the past and were treated for freezing. Equex-STM paste was contained in both the 1st(3%) and the 2nd(7%) diluent and the 2nd diluent was added to the 1st diluent following glycerol equilibration for an hour and a half. To investigate the effect of Equex-STM paste in the extender on post-thaw canine sperm characteristics, the post-thaw viability, motility, and HOS(Hypoosmotic swelling) values were evaluated according to the different composition of extender with or without Equex-STM paste, thawing conditions, and different thawing media added to thawed semen. 1. Canine sperm removed from seminal plasma and frozen )n Sweden extender containing Equex showed higher post-thaw viability, motility, and HOS values than those frozen in the extender containing Equex-STM paste with seminal plasma and those frozen in the extender without Equex and seminal plasma. 2. Canine sperm frozen in Sweden extender containing Equex-STM paste with 5% glycerol showed higher post-thaw viability, motility, and HOS values than those frozen with 3%, 8% glycerol or 5% DMSO. 3. The canine semen frozen in Sweden extender with 5% glycerol and Equex-STM paste showed higher viability, motility, and HOS values when thawed at $70^{\circ}C$ for 8 seconds than when thawed at $37.5^{\circ}C$ for 1 min and at $18-20^{\circ}C$ for 5 min. 4. TFC (tris -fructose-citrate) and PB S (phosphate buffered saline) medium added immediately to thawed canine semen brought better viability, motility, and HOS values for the sperm than those semen added with TGC(tris-glucose-citrate) and no medium. These results indicated that Equex-STM paste in Sweden extender for freezing the canine sperm which were removed from seminal plasma brought good post-thaw viability and motility of canine sperm. Also of the freezing conditions of canine sperm with the same extender containing Equex, the concentration of 5% glycerol, the thawing condition at $70^{\circ}C$ for 8 sec, and TFC and PBS medium added to the thawed semen brought better post-thaw viability and motility of canine sperm than the other conditions used in this study.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.957-960
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• 2006

In order to predict the accumulated damages by cyclic freeze-thaw, a regression analysis by the Response Surface Method (RSM) is used. RSM has merits when the other probabilistic simulation techniques can not guarantee the convergence of probability of occurrence or when the others can not differentiate the derivative terms of limit state functions, which are composed of random design variables in the model of complex system or the system having higher reliability. For composing limit state function, the important parameters for cyclic freeze-thaw-deterioration of concrete structures, such as water to cement ratio, entrained air pores, and the number of cycles of freezing and thawing, are used as input parameters of RSM. The predicted results of relative dynamic modulus and residual strains after 300 cycles of freeze-thaw for specimens show very good agreements with the experimental results. The RSM result can be used to predict the probability of occurrence for designer specified critical values. Therefore, it is possible to evaluate the life cycle management of concrete structures considering the accumulated damages by the cyclic freeze-thaw by the use of proposed prediction method.

• 한국지형학회지
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• 제19권3호
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• pp.109-121
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• 2012

한라산 정상의 백록담 서북벽 표고 1,860m 지점에서 18개월간 용암돔 암벽의 표면 온도를 향별로 관측하여 동결융해 사이클의 빈도와 출현 시기, 동결기의 암온 저하량을 밝혔다. 관측 지점에는 일주기와 연주기의 동결융해 사이클이 나타난다. 유효동결융해 사이클을 포함하여 일주기성 동결융해 사이클은 북동향 암벽보다 남서향 암벽에서 더 많이 발생한다. 일주기성 동결융해 사이클은 남서향 암벽에서는 2월과 3월에, 북동향 암벽에서는 11월과 4월에 집중적으로 출현한다. 또한 남서향 암벽에서는 11월 중순~4월 중순, 북동향 암벽에서는 11월 초순~4월 하순에 걸쳐 $0^{\circ}C$ 이하의 암온이 지속되는 계절적 동결기가 출현함으로써 연주기성 동결융해 사이클도 확인된다. 동결기의 암온 저하량은 동결지수가 더 높은 북동향 암벽에서 더 크고, 동결파쇄의 최적 온도 기준점으로 알려진 $-3^{\circ}C$ 이하의 지속시간도 북동향 암벽에서 더 길어 북동향 암벽이 남서향 암벽보다 일주기성 동결융해 사이클의 빈도는 낮아도 동결 강도는 더 큰 것으로 보인다. 따라서 암벽의 향에 따른 일사 조건의 차이가 동결융해 사이클의 빈도와 동결 지속시간을 결정함으로써 일주기성 동결융해 사이클은 남서향 암벽에서, 연주기성 동결융해 사이클은 북동향 암벽에서 현저하게 출현한다. 암석의 동결파쇄는 온도 조건으로만 결정되는 것은 아니므로 식생피복, 지형적 위치, 고도, 향을 달리하는 다양한 장소의 온도 자료 축적과 함께 암석 물성과 수분 공급에 관한 조사가 필요하다.

• Food Science and Biotechnology
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• 제16권4호
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• pp.520-525
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• 2007

The physicochemical properties of sun-dried and cyclic freeze-thaw dried Alaska pollack were analyzed to compare the 2 drying processes. The moisture content and water activity of sun-dried Alaska pollack were higher than cyclic freeze-thaw dried and 1 year-aged cyclic freeze-thaw dried Alaska pollack (hwangtae). The relatively low temperatures used in cyclic freeze-thaw drying retards lipid oxidation compared to sun drying based on the acid and peroxide values, and the levels of thiobarbituric acid-reactive substances (TBARS) in the dried fish. The water holding capacity of cyclic freeze-thaw dried Alaska pollack aged for 1 year (hwangtae) under ambient conditions at the drying location was higher than that of sun-dried Alaska pollack. The swelling of myofibrilar filaments during cyclic freeze-thaw drying may be responsible for the softening of the dried muscle protein. Aging the cyclic freeze-thaw dried Alaska pollack for 1 year contributed to an increased yellowish color of the hwangtae.

• 한국가축번식학회지
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• 제23권2호
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• pp.165-174
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• 1999

본 연구는 동결융해 후 정자의 생존성에 영향을 미치는 요인을 찾기 위하여 수행하였다. 동결융해 후 생존성에 대한 요인으로써 동결보존액, 동해보호제, 예비동결법 및 동결소요시간을 비교하였다. 동결과정중 정액의 질을 평가하기 위하여 활력, NAR 및 생존율을 조사한 결과는 다음과 같다. 돼지정액을 BF5, LYE, Soejima 및 modified Soejima 보존액으로 동결하였을 때 동결융해 후 정자활력은 M-Soejima 보존액이 44.5$\pm$6.4%로 다소 높았다. M-Soejima 보존액의 2차 회석액에 caffeine(2mM), heparin(l00 ${\mu}\ell$/$m\ell$) 및 caffeine＋heparin 를 첨가하였을 때 동결융해 후 활력은 caffeine 첨가구가 61.7% 로 가장 높았으며, 단독 혹은 혼합첨가가 첨가하지 않은 대조구보다 유의적으로 높은 활력을 나타내었다 (p＜0.05). M-Soejima 보존액에 동해보호제로서 glycerol(Gly), ethylene glycol(EG), propylene glycol(GP), Gly＋EG 및 Gly＋PG을 첨가하였을 때 동결융해 후 활력 및 NAR 율은 Gly＋PG의 혼합첨가시 (31.3%/39.5%) 가 다른 첨가구보다 다소 높았으며 생존율은 Gly＋EG 첨가구가 21.2% 로 다른 첨가구보다 다소 높았다. BE5와 M-Soejima 보존액으로 straw 및 pellet 동결법으로 동결하는 동안 dry ice-pellet, dry ice-straw 및 L$N_2$vapor-straw 법으로 예비동결하였을 때 각각 22.8, 47.5, 52.5% 및 42.5, 47.5, 57.5% 의 활력을 나타내었다. 또한 M-Soejima 보존액의 straw 법으로 l차 희석부터 동결완료까지 소요되는 시간을 2, 5 및 7시간으로 하였을 때 동결융해 후 활력 및 생존율은 처리간에 큰 차이가 없었으나, NAR 율은 처리시간이 길어질수록 다소 높은 경향을 나타내었다. 이러한 결과로 미루어 볼 때 동결융해 후 활력, NAR 및 생존율을 높이기 위해서는 caffeine 이 첨가된 M-Soejima 보존액에 동해보호제로 glycerol과 propylene glycol 또는 ehtylene glycol 을 사용하여 2시간 동안 빠르게 동결처리된 정액이 다소 유리할 것으로 사료되었다.

• 한국식품영양학회지
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• 제11권4호
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• pp.409-415
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• 1998

This study was carried out to investigate the effects of freezing temperature on quality of vacuum packaging freezed beef. In case of thaw drip loss, the freezing of -3$^{\circ}C$ and -20$^{\circ}C$ were 5.23% and 5.17% to 60 days respectively, were increased significantly during freezing. The cooking loss of water bath and pan were increased significantly during freezing than the beginning of freezing, but were no different between -3$^{\circ}C$ and -20$^{\circ}C$. The salt soluble protein extractability was decreased during freezing, the -20$^{\circ}C$ freezing was higher than -3$^{\circ}C$freezing. The water soluble protein extractability was increased during freezing higher than during freezing. The myoglobin denatured percentage of the -3$^{\circ}C$ freezing was higher than -20$^{\circ}C$ freezing, the 15 days storage of -3$^{\circ}C$ freezing was highest to 96%. The shear force value was not change during freezing, the myofibrillar fragmentation index during freezing was higher than the beginning of freezing, but was not change during freezing. The pH was decreased to freezing 45 days, after that increased.

• Computers and Concrete
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• 제21권2호
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• pp.209-217
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• 2018

The dynamic compressive behavior of concrete after freezing and thawing tests are investigated by using the split Hopkinson pressure bar (SHPB) technique. The stress-strain curves of concrete under dynamic loading are measured and analyzed. The setting numbers of freeze-thaw cycles are 0, 25, 50, and 75 cycles. Test results show that the dynamic strength decreases and peak strain increases with the increasing of freeze-thaw cycles. Based on the Weibull distribution model, statistical damage constitutive model for dynamic stress-strain response of concrete after freeze-thaw cycles was proposed. At last, the fragmentation test of concrete subjected to dynamic loading and freeze-thaw cycles is carried out using sieving statistics. The distributions of the fragment sizes are analyzed based on fractal theory. The fractal dimensions of concrete increase with the increasing of both freeze-thaw cycle and strain rate. The relations among the fractal dimension, strain rates and freeze-thawing cycles are developed.

• Fisheries and Aquatic Sciences
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• 제24권2호
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• pp.63-77
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• 2021

The aim of this research was to investigate different factors, including cryoprotective agents (CPAs), diluents, dilution ratios, equilibrium times, freezing rates, and thawing methods to optimize cryopreservation protocols for large yellow croaker (Larimichthys crocea). The parameters evaluated were sperm motility, sperm activity index (SAI), survival rate, and DNA damage. Different types of CPAs, such as dimethyl sulfoxide (DMSO), propylene glycol (PG), ethylene glycol (EG), methanol, and glycerol, were tested for sperm preservation. The highest motility, SAI, and survival rate were observed when EG was used. Different diluents such as Stein's solution, Hank's balanced salt solution, marine fish Ringer's solution, artificial seminal plasma (ASP) of small yellow croaker, and Cortland solution were investigated. The highest post-thaw motility was observed upon using ASP as the diluent. Different concentrations of EG were then mixed with ASP to identify the optimal EG concentration. Experimental results showed that the motility (70.33 ± 1.20%), SAI (5), and survival rate (78.30 ± 0.42%) of post-thaw sperm were optimum when 10% EG and ASP were used as the CPA and diluent of cryopreservation, respectively. Post-thaw sperm motility was high at equilibration times below 150 s and at an optimum dilution ratio of 1:1 (sperm: CPA + diluent) and was not significantly different compared with fresh sperm motility. The freezing rate was found to be slow below -10℃/min. The thawing temperature of 45℃ was identified as ideal. The percentage of tail DNA in post-thaw sperm at 10% EG and ASP was also investigated and was found to have more significant DNA damage than that in fresh sperm but significantly lower damage than that in post-thaw sperm at EG concentrations of 5%, 15%, and 20% (p < 0.05). The cryopreservation protocols obtained in this study will be useful in large yellow croaker hatcheries.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.761-764
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• 2006

Nowadays, It is openly reported that concrete structures have been attacted by freez and thaw. However, it is not clearly defined how to understand & measure the test method of freez and thaw of concrete structures. Thus, in this strudy, We performed the research with the test results using provision of ASTM C672 of freez and thaw durability of concrete. Also, it is identified suitable test method to measure of freez and thaw.